• 제목/요약/키워드: Ns

검색결과 2,503건 처리시간 0.033초

dicA promoter DNA에 붙는 H-NS 단백질에 의한 dicA 유전자의 발현 조절 (H-NS binding on dicA promoter DNA inhibits dicA gene expression)

  • 윤상훈;이연호;임헌만
    • 미생물학회지
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    • 제55권3호
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    • pp.191-198
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    • 2019
  • H-NS는 대장균에서 DNA 결합 단백질로 수많은 유전자의 발현에 영향을 주는 것으로 잘 알려져 있다. DicA 단백질은 dicF, dicB의 발현을 억제하여 대장균의 분열을 조절한다. dicA의 발현에 Cnu, H-NS의 관여 여부는 CnuK9E 돌연변이가 $37^{\circ}C$에서 dicA의 발현을 억제하여 대장균이 길게 자라는 현상을 일으키며 처음 알려졌다. 하지만 Cnu와 H-NS 두 단백질이 어떻게 dicA의 발현을 조절하는지에 대한 분자적인 기작 연구는 잘 되어있지 않다. 본 연구에서 H-NS가 dicA와 dicC 유전자의 프로모터 부근에 염기서열 특이적으로 결합하며, $37^{\circ}C$ 보다 $25^{\circ}C$에서 DNA 더 잘 결합하는 것을 확인하였다. 그리고 EMSA를 통해 Cnu는 H-NS의 DNA 결합의 oligomeric state를 변화시키는 방식으로 작용하는 것을 보여주었다. In vivo transcription assay와 real time PCR을 통해 H-NS가 제거된 대장균에서 dicA 프로모터 활성이 높아지고, 분열 초기 dicA의 발현이 조절 받지 못하고 증가하는 것으로 보아, H-NS는 dicA의 발현에 억제자로서 기능한다.

한국 프로축구 선수들의 영양보충제 섭취 실태 (The Use of Nutritional Supplements in Korean Elite Soccer Players)

  • 이현숙
    • Journal of Nutrition and Health
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    • 제39권3호
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    • pp.299-306
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    • 2006
  • This study was done to investigate the use of nutritional supplements (NS) in Korean elite soccer players using an anonymous questionnaire. NS were classified into health supplements, manufactured health food supplements, chinese medicines & tonic foods, and nutrient supplements. Information was sought on the type of NS and factors that might influence supplement use including selected demographic parameters and health related variables. The data were collected from 241 athletes (aged $24.6{\pm}3.8$ years) in 9 professional soccer club. The prevalence of NS use among the subjects was 81.3%. Health supplements were used most frequently and nutrient supplement drug was the second one. Among the health supplements, weight/muscle gainer and calorie replacement product were most frequently used. Vitamin supplements were most frequently used among all nutrient supplement drugs. Users of NS were higher age (p<0.05) duration of exercise (p<0.05), and income (p<0.05) than non-users. The married (p<0.05) and a member of K-league (p<0.01) tended to have higher prevalence of NS use. The main adviser of NS were family (55.3%) and oneself (39%) instead of coach or sports nutritionist. Although NS use, only 26.2% certainly check up nutritional information on their used NS. Among the subjects, 84.5% of them felt that NS use were improved athletic performance, and 86.5% of them will to keep on taking supplement. These data suggest that a large number of elite soccer players use NS and these players may require education about healthy nutritional supplement practice and on the proper use of nutritional supplements.

CsI:X(X=Li+,K+,Rb+단결정의 섬광특성 (Scintillation Characteristics of CsI:X(X=Li+,K+,Rb+ Single Crystals)

  • 강갑중;도시홍;이우교;오문영
    • 센서학회지
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    • 제12권1호
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    • pp.1-9
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    • 2003
  • CsI에 활성제로 Li, K, Rb를 첨가하여 CsI(Li), CsI(K) 및 CsI(Rb) 단결정을 Czochralski방법으로 육성하였다. $^{137}CS$(0.662 MeV)에 대한 CsI(Li:0.2 mole%) 섬광체의 에너지 분해능은 14.5%이었고 CsI(K:0.5 mole%) 섬광체는 15.9%이었으며 CsI(Rb:1.5 mole%) 섬광체는 17.0%이였다. 이들 CsI(Li), CsI(K) 및 CsI(Rb) 섬광체의 $\gamma$선 에너지에 대한 에너지 교정곡선은 선형적 이였다. 일정비율 시간분석법(CFT :constant-fraction timing method)으로 측정한 CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 성광체의 시간 분해능은 각각 9.0 ns, 14.7 ns 및 9.7 ns이였다. CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 섬광체의 형광감쇠시간은 각각 ${\tau}_1=41.2\;ns$, ${\tau}_2=483\;ns$, ${\tau}_1=47.2\;ns$, ${\tau}_2=417\;ns$${\tau}_1=41.3\;ns$${\tau}_2=553\;ns$이였다. 그리고 CsI(Li:0.2 mole%), CsI(K:0.5 mole%) 및 CsI(Rb:1.5 mole%) 단결정의 인광감쇠시간은 각각 0.51 s, 0.57 s 및 0.56 s이였다.

Acute kidney injury in childhood-onset nephrotic syndrome: Incidence and risk factors in hospitalized patients

  • Kim, Mi Young;Cho, Myung Hyun;Kim, Ji Hyun;Ahn, Yo Han;Choi, Hyun Jin;Ha, Il Soo;Cheong, Hae Il;Kang, Hee Gyung
    • Kidney Research and Clinical Practice
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    • 제37권4호
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    • pp.347-355
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    • 2018
  • Background: Nephrotic syndrome (NS) is the most common glomerulopathy in children. Acute kidney injury (AKI) is a common complication of NS, caused by severe intravascular volume depletion, acute tubular necrosis, interstitial nephritis, or progression of NS. However, the incidence and risk factors of childhood-onset NS in Korea are unclear. Therefore, we studied the incidence, causes, and risk factors of AKI in hospitalized Korean patients with childhood-onset NS. Methods: We conducted a retrospective review of patients with childhood-onset NS who were admitted to our center from January 2015 to July 2017. Patients with decreased renal function or hereditary/secondary NS, as well as those admitted for management of other conditions unrelated to NS, were excluded. Results: During the study period, 65 patients with idiopathic, childhood-onset NS were hospitalized 90 times for management of NS or its complications. Of these 90 cases, 29 met the Kidney Disease Improving Global Outcomes criteria for AKI (32.2%). They developed AKI in association with infection (n = 12), NS aggravation (n = 11), dehydration (n = 3), and intravenous methylprednisolone administration (n = 3). Age ${\geq}9$ years at admission and combined use of cyclosporine and renin-angiotensin system inhibitors were risk factors for AKI. Conclusion: AKI occurred in one-third of the total hospitalizations related to childhood-onset NS, owing to infection, aggravation of NS, dehydration, and possibly high-dose methylprednisolone treatment. Age at admission and use of nephrotoxic agents were associated with AKI. As the AKI incidence is high, AKI should be considered during management of high-risk patients.

Molecular and Structural Characterization of the Domain 2 of Hepatitis C Virus Non-structural Protein 5A

  • Liang, Yu;Kang, Cong Bao;Yoon, Ho Sup
    • Molecules and Cells
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    • 제22권1호
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    • pp.13-20
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    • 2006
  • Hepatitis C virus (HCV) non-structural protein 5A protein (NS5A), which consists of three functional domains, is involved in regulating viral replication, interferon resistance, and apoptosis. Recently, the three-dimensional structure of the domain 1 was determined. However, currently the molecular basis for the domains 2 and 3 of HCV NS5A is yet to be defined. Toward this end, we expressed, purified the domain 2 of the NS5A (NS5A-D2), and then performed biochemical and structural studies. The purified domain 2 was active and was able to bind NS5B and PKR, biological partners of NS5A. The results from gel filtration, CD analysis, 1D $^1H$ NMR and 2D $^1H-^{15}N$ heteronuclear single quantum correlation (HSQC) spectroscopy indicate that the domain 2 of NS5A appears to be flexible and disordered.

The Influence of Alpha-fetoprotein on Natural Suppressor Cell Activity and Ehrlich Carcinoma Growth

  • Belyaev, Nikolai Nikolaevich;Bogdanov, Andrei-Yurievich;Savvulidi, PhiIipp-Gorgievich;Krasnoshtanov, Vladimir-Konstantinovich;Tleulieva, Raikhan-Tleulievna;Alipov, Gabit-Kaimovich;Sekine, Ichiro;Bae, Jun-Sang;Lee, Jeong-Beom;Min, Young-Ki;Yang, Hun-Mo
    • The Korean Journal of Physiology and Pharmacology
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    • 제12권4호
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    • pp.193-197
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    • 2008
  • The influence of alpha-fetoprotein (AFP) on the bone marrow (BM) natural suppressor (NS) cells of intact Ehrlich carcinoma -bearing CBA mice was studied. Bone marrow NS cells were fractionated into three fractions by isopycnic centrifugation on percoll gradients: NS1 (${\rho}$=1.080 g/ml), NS2 (${\rho}$=1.090 g/ml) and NS3 (1.100> ${\rho}$ > 1.090 g/ml). These fractions were highly different in their sensitivity to known NS cell inductors (interleukin (IL)-2, IL-3 or histamine). None of the NS fractions isolated from the intact mice spontaneously produced antiproliferative activity, however, they showed a high level of NS (antiproliferative and natural killer cell inhibitory) activity under the influence of AFP. A single injection of AFP to intact mice led to an increase of spontaneous NS activity and the inhibition of natural killer cell activity. NS activity, especially NS2, was increased in when tumor cells were subcutaneously inoculated three days after AFP injection. In the AFP-treated mice, the tumor mass at 14 days was 60% larger than that in the untreated mice. Our data confirmed that AFP is a tumor marker that can inhibit cancer immunity and plays a role in cancer pathogenesis.

Divergence of Genes Encoding Non-specific Lipid Transfer Proteins in the Poaceae Family

  • Jang, Cheol Seong;Jung, Jae Hyeong;Yim, Won Cheol;Lee, Byung-Moo;Seo, Yong Weon;Kim, Wook
    • Molecules and Cells
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    • 제24권2호
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    • pp.215-223
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    • 2007
  • The genes encoding non-specific lipid transfer proteins (nsLTPs), members of a small multigene family, show a complex pattern of expressional regulation, suggesting that some diversification may have resulted from changes in their expression after duplication. In this study, the evolution of nsLTP genes within the Poaceae family was characterized via a survey of the pseudogenes and unigenes encoding the nsLTP in rice pseudomolecules and the NCBI unigene database. nsLTP-rich regions were detected in the distal portions of rice chromosomes 11 and 12; these may have resulted from the most recent large segmental duplication in the rice genome. Two independent tandem duplications were shown to occur within the nsLTP-rich regions of rice. The genomic distribution of the nsLTP genes in the rice genome differs from that in wheat. This may be attributed to gene migration, chromosomal rearrangement, and/or differential gene loss. The genomic distribution pattern of nsLTP genes in the Poaceae family points to the existence of some differences among cereal nsLTP genes, all of which diverged from an ancient gene. The unigenes encoding nsLTPs in each cereal species are clustered into five groups. The somewhat different distribution of nsLTP-encoding EST clones between the groups across cereal species imply that independent duplication(s) followed by subfunctionalization (and/or neofunctionalization) of the nsLTP gene family in each species occurred during speciation.

Nonsaponin fraction of Korean Red Ginseng attenuates cytokine production via inhibition of TLR4 expression

  • Ahn, Huijeong;Han, Byung-Cheol;Kim, Jeongeun;Kang, Seung Goo;Kim, Pyeung-Hyeun;Jang, Kyoung Hwa;So, Seung Ho;Lee, Seung-Ho;Lee, Geun-Shik
    • Journal of Ginseng Research
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    • 제43권2호
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    • pp.291-299
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    • 2019
  • Background: Ginsenosides of Korean Red Ginseng extracts (RGE) and its saponin components suppress secretion of inflammasome-mediating cytokines, whereas the nonsaponin fraction (NS) of RGE oppositely stimulates cytokine secretion. Although direct exposure of NS to macrophages in mice induces cytokine production, oral administration of NS has not been studied in inflammasome-related disease in animal models. Methods: Mice were fed RGE or NS for 7 days and then developed peritonitis. Peritoneal cytokines were measured, and peritoneal exudate cells (PECs) were collected to assay expression levels of a set of toll-like receptors (TLRs) and cytokines in response to NS ingestion. In addition, the role of intestinal bacteria in NS-fed mice was assessed. The effect of preexposure to NS in bone marrow-derived macrophages (BMDMs) on cytokine production was further confirmed. Results: NS ingestion attenuated secretion of peritoneal cytokines resulting from peritonitis. In addition, the isolated PECs from NS-fed mice presented lower TLR transcription levels than PECs from control diet-fed mice. BMDMs treated with NS showed downregulation of TLR4 mRNA and protein expression, which was mediated by the $TLR4-MyD88-NF{\kappa}B$ signal pathway. BMDMs pretreated with NS produced less cytokines in response to TLR4 ligands. Conclusion: NS administration directly inhibits TLR4 expression in inflammatory cells such as macrophages, thereby reducing secretion of cytokines during peritonitis.

아미노실란과 이온성 액체로 표면 기능화된 실리카에 담지된 메탈로센 촉매 합성 및 에틸렌 중합 (Preparation of Metallocene Catalysts Supported on Aminosilane and Ionic Liquids Functionalized Silica and its Ethylene Polymerization)

  • 임진형;이정숙;고영수
    • 폴리머
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    • 제39권1호
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    • pp.169-173
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    • 2015
  • 3-Aminopropyltrimethoxysilane(1NS) 또는 N-[3-(trimethoxysilyl)propyl]ethylenediamine(2NS)으로 표면 기능화된 실리카에 1-butyl-4-methylpyridinium chloride(Cl)와 tributylmethylammonium chloride(Amm), benzyldimethyltetradecylammonium chloride(Ben), 1-butyl-1-methylpyrrolidinium chloride(Pyr)와 같은 이온성 액체를 이용하여 표면처리한 후 메탈로센 촉매를 담지하여 에틸렌 중합을 실시하였다. $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ 촉매와 $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$ 촉매의 Zr 함량은 아미노실란 화합물로만 표면 처리된 촉매보다 감소하였다. $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ 촉매의 중합 활성은 $SiO_2/1NS/(n-BuCp)_2ZrCl_2$ 촉매보다 증가하였다. 반면, $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$은 Zr 함량의 감소로 중합 활성은 $SiO_2/2NS/(n-BuCp)_2ZrCl_2$ 촉매에 비해 감소하였다.

Effect of Morphology and Dispersibility of Silica Nanoparticles on the Mechanical Behaviour of Cement Mortar

  • Singh, Lok Pratap;Goel, Anjali;Bhattachharyya, Sriman Kumar;Ahalawat, Saurabh;Sharma, Usha;Mishra, Geetika
    • International Journal of Concrete Structures and Materials
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    • 제9권2호
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    • pp.207-217
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    • 2015
  • The influence of powdered and colloidal nano-silica (NS) on the mechanical properties of cement mortar has been investigated. Powdered-NS (~40 nm) was synthesized by employing the sol-gel method and compared with commercially available colloidal NS (~20 nm). SEM and XRD studies revealed that the powdered-NS is non-agglomerated and amorphous, while colloidal-NS is agglomerated in nature. Further, these nanoparticles were incorporated into cement mortar for evaluating compressive strength, gel/space ratio, portlandite quantification, C-S-H quantification and chloride diffusion. Approximately, 27 and 37 % enhancement in compressive strength was observed using colloidal and powdered-NS, respectively, whereas the same was up to 19 % only when silica fume was used. Gel/space ratio was also determined on the basis of degree of hydration of cement mortar and it increases linearly with the compressive strength. Furthermore, DTG results revealed that lime consumption capacity of powdered-NS is significantly higher than colloidal-NS, which results in the formation of additional calcium-silicate-hydrate (C-S-H). Chloride penetration studies revealed that the powdered-NS significantly reduces the ingress of chloride ion as the microstructure is considerably improved by incorporating into cement mortar.